Function vm_object_page_collect_flush

freebsd/vm/vm_object.c:1111–1152

}

static int
vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags,
    int flags, boolean_t *allclean, boolean_t *eio)
{
	vm_page_t ma[vm_pageout_page_count], p_first, tp;
	int count, i, mreq, runlen;

	vm_page_lock_assert(p, MA_NOTOWNED);
	vm_page_assert_xbusied(p);
	VM_OBJECT_ASSERT_WLOCKED(object);

	count = 1;
	mreq = 0;

	for (tp = p; count < vm_pageout_page_count; count++) {
		tp = vm_page_next(tp);
		if (tp == NULL || vm_page_tryxbusy(tp) == 0)
			break;
		if (!vm_object_page_remove_write(tp, flags, allclean)) {
			vm_page_xunbusy(tp);
			break;
		}
	}

	for (p_first = p; count < vm_pageout_page_count; count++) {
		tp = vm_page_prev(p_first);
		if (tp == NULL || vm_page_tryxbusy(tp) == 0)
			break;
		if (!vm_object_page_remove_write(tp, flags, allclean)) {
			vm_page_xunbusy(tp);
			break;
		}
		p_first = tp;
		mreq++;
	}

	for (tp = p_first, i = 0; i < count; tp = TAILQ_NEXT(tp, listq), i++)
		ma[i] = tp;

	vm_pageout_flush(ma, count, pagerflags, mreq, &runlen, eio);
	return (runlen);
}

/*
 * Note that there is absolutely no sense in writing out